Nitric oxide and heat shock protein 90 activate soluble guanylate cyclase by driving rapid change in its subunit interactions and heme content

Background: Heme insertion into souble guanylate cyclase (sGC) enables it to bind nitric oxide (NO) for cell signaling. Results: NO triggered a rapid, reversible, and hsp90-dependent heme insertion into sGC-β1 and an association with sGC-α1 subunit. sGC activator BAY 60-2770 did the same. Conclusion: NO dynamically impacts the maturation and stability of active sGC heterodimer. Significance: The data uncover new mechanisms that regulate cellular NO signaling cascades.